DTS imaging with a Digitally Addressable X-ray Source (DAXS) Abstract 4-D x-ray imaging would provide a powerful tool for imaging procedures involving contrast injection or anatomical motions. In this research, we propose to develop and investigate a 4-D x-ray imaging system based on digital tomosynthesis (DTS) and a digitally addressable x-ray source (DAXS). The DAXS allows x-rays to be generated at any digitally selected location on a flat x-ray panel. This would enable us to design and construct a stationary DTS system that contains no moving parts. Due to the elimination of physically moving parts, the scan speed can be substantially increased, thus allowing for 4-D imaging, with which 3-D images of moving anatomy or injected contrast materials can be imaged and monitored. The use of a DAXS also allows the x-ray source to be digitally shifted with a 2-D pattern, leading to more effective blurring of the out of focal plane objects and better contrast of the in plane objects. The proposed research consists of two major parts carried out at two different sites: Stellarray Inc., a subsidiary of Stellar Micro Devices, Inc. (SMD) at Austin, TX and the Digital Imaging Research Laboratory (DIRL) at the U. of Texas M. D. Anderson Cancer Center (MDACC) at Houston, TX. The closeness of the two sites encourages active collaboration and interaction. In this Academic-Industry collaboration, the DAXS technology will be developed at SMD and provided to MDACC-DIRL to implement and investigate the DTS techniques for 4-D imaging. Operation parameters and image quality metrics will be investigated and optimized. Phantom experiments will be performed to demonstrate and validate the proposed 4-D x-ray imaging techniques. In this collaboration, there will be a separate Principal Investigator (PI) at each site. The MDACC PI will also serve as the contact and coordinating PI.